[Clear cell sarcoma of the hand. Description of a case].

Clear cell sarcoma of the hand. Case report. Histologic, ultrastructural and immunohistochemical features of a case of clear cell sarcoma (also called malignant melanoma of soft parts) arisen in the index finger of the right hand in a 28 year-old-woman are described in this report. Typical forms of this tumor are deeply located and associated with tendons and aponeuroses, lacking cutaneous involvement. The tumor has to be differentiated from other benign and malignant lesions of the soft parts, such as a giant cell tumor of tendon sheaths and a fibrosarcoma. The demonstration of melanin and a positive immunohistochemical reaction for S-100 protein and HMB-45 (a melanin-associated antigen) can assist in the differential diagnosis. In spite of a slow and protracted clinical course, many of the patients experience multiple local recurrences and distant metastases. Prognosis is poor in a high percentage of cases.